Disorder to order transition in cell-ECM systems mediated by cell-cell collective interactions

Area of Science:

• Cell Biology
• Biophysics
• Biomaterials Science

Background:

• Cells in tissues perform collective activities for processes like wound healing and organogenesis.
• The initiation of complex collective cellular processes remains unclear.

Purpose of the Study:

• To investigate how cells initiate collective behavior in a 3D extracellular matrix (ECM).
• To understand the mechanism behind the transition from disordered to ordered cellular dynamics.

Main Methods:

• Utilized free-floating (FF) 3D collagen gels with embedded fibroblasts as a model system.
• Analyzed cell-ECM network formation and gel compaction as a function of cell-cell distance.
• Observed cell dynamics and ECM remodeling within and beyond a critical distance.

Main Results:

• Cells form a cell-ECM network and remodel the matrix irreversibly within a critical distance.
• Beyond the critical distance, cells exhibit transient matrix deformation without memory, maintaining disorder.
• A sharp transition in gel compaction was observed, similar to phase transitions in materials.

Conclusions:

• Network formation is a necessary and sufficient condition for triggering collective cellular behavior and a disorder-to-order transition.
• This study reveals a link between cell dynamics, ECM microstructure, and collective action.
• Findings offer insights into pathological processes (cancer, wound healing) and biomaterial engineering.